Hot/cold test equipment for nand flash memory with dehumidifying function

ABSTRACT

Disclosed herein is hot/cold test equipment for a Nand Flash Memory. The test equipment includes a mounting unit that contains the Nand Flash Memory together with a socket to test whether the memory is defective or not, a chamber provided above the mounting unit and moving up and down to come into contact with the socket and thereby provide a target temperature, and a temperature display displaying the target temperature. The chamber includes a block inserted into the socket, a thermoelectric element seated on an upper portion of the block, a water jacket seated on an upper portion of the thermoelectric element and circulating cooling water therein, and a cooling fan provided in the water jacket to blow air downwards, with a discharge hole being formed on a lower surface of the block to discharge nitrogen gas.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention relates, in general, to test equipment for NandFlash Memory and, more particularly, to hot/cold test equipment with adehumidifying function, capable of performing a cold test as well as ahot test.

2. Description of the Related Art

The most difficult problem with the semiconductor production process isthe requirement for temperature test equipment that is accurate andrapid. To address this problem, there is an urgent need for temperaturetest equipment that can maximize productivity.

However, such test equipment incurs a problem related to highefficiency. Thus, in recent years, owing to developments innano-technology made because of various studies, research into athermoelectric element field capable of implementing clean energy isbeing actively conducted. Therefore, there is a need to developtemperature test equipment using the thermoelectric element at low costwith high efficiency.

Further, until now, a hot test was mainly performed but a cold test wasnot performed, as a temperature test. Therefore, people want to developtemperature test equipment capable of performing the cold test as wellas the hot test while using the thermoelectric element.

SUMMARY OF THE INVENTION

Accordingly, the present invention has been made keeping in mind theabove problems occurring in the prior art, and an object of the presentinvention is to provide hot/cold test equipment using a thermoelectricelement, which can moreover prevent humidity from occurring in a coldtest.

In order to accomplish the above object, the present invention provideshot/cold test equipment for a Nand Flash Memory, including a mountingunit that contains the Nand Flash Memory together with a socket to testwhether the memory is defective or not, a chamber provided above themounting unit and moving up and down to come into contact with thesocket and thereby provide a target temperature, and a temperaturedisplay displaying the target temperature, wherein the chamber includesa block inserted into the socket, a thermoelectric element seated on anupper portion of the block, a water jacket seated on an upper portion ofthe thermoelectric element and circulating cooling water therein, and acooling fan provided in the water jacket to blow air downwards, with adischarge hole being formed on a lower surface of the block to dischargenitrogen gas.

Further, the present invention provides hot/cold test equipment for aNand Flash Memory, including a mounting unit that contains the NandFlash Memory together with a socket to test whether the memory isdefective or not, a chamber provided above the mounting unit and movingup and down to come into contact with the socket and thereby provide atarget temperature, and a temperature display displaying the targettemperature, wherein the chamber includes a block inserted into thesocket, a thermoelectric element seated on an upper portion of theblock, a heat pipe seated on an upper portion of the thermoelectricelement, a radiator seated on an upper portion of the heat pipe, and aradiation fan disposed above the radiator to blow air downwards.

The block may be elastically supported in the chamber.

Further, the socket may include an adapter with which a lower end of theblock comes into contact, and pinholes may be preferably formed in abottom of the adapter to cause pins of the socket to protrude towardsthe block, come into contact with an interface of the Nand Flash Memorypressed by the block and then provide various electricalcharacteristics, when the block is pressed against the adapter.

The hot/cold test equipment may further include a nitrogen generatorprovided under the mounting unit to supply the nitrogen gas to thedischarge hole.

Further, preferably, the block may include an upper block that comesinto contact with a lower portion of the thermoelectric element, and alower block that is coupled to a lower portion of the upper block and isinserted into the socket, and the heat pipe may be provided between theupper block and the lower block, and a temperature sensor may beprovided in an interior adjacent to a bottom of the lower block to beconnected to the temperature display.

Furthermore, outer portions of the block and the thermoelectric elementmay be surrounded by an insulator.

Further, a wick made of copper may be provided in the heat pipe in sucha way as to extend from an evaporation portion to a middle portion ofthe heat pipe.

BRIEF DESCRIPTION OF THE DRAWINGS

The above and other objects, features and advantages of the presentinvention will be more clearly understood from the following detaileddescription taken in conjunction with the accompanying drawings, inwhich:

FIG. 1 is a perspective view showing test equipment according to thepresent invention;

FIG. 2 is a front view showing the test equipment of FIG. 1;

FIG. 3 is a detailed view showing a socket of FIG. 1;

FIG. 4 is a view showing an interior of a chamber for a cold test;

FIG. 5 is a view showing an interior of a chamber for a hot test;

FIG. 6 is a view showing the test equipment according to the presentinvention, in which it further includes a nitrogen generator;

FIG. 7 is a view showing an inner structure of a heat pipe used in thepresent invention; and

FIG. 8 is a sectional view showing a portion having a wick in FIG. 7.

DESCRIPTION OF PREFERRED EMBODIMENTS

Hereinafter, hot/cold test equipment for Nand Flash Memory with adehumidifying function according to a preferred embodiment of thepresent invention will be described with reference to the accompanyingdrawings.

Referring to FIGS. 1 and 2, hot/cold test equipment 100 according to thepresent invention includes a mounting unit 110, a chamber 130 and atemperature display 160 in the order of going from a lower position toan upper position.

The mounting unit 110 contains the Nand Flash Memory to be tested, andapplies electricity to the memory to determine whether the memory isdefective or not. A plurality of sockets 115 is mounted on an uppersurface of such a mounting unit 110, and memories are put into thecorresponding sockets 115.

The chamber 130 above the mounting unit 110 moves along vertical guides120 downwards to the mounting unit 110 to be in close contact therewith,or upwards from the mounting unit 110 to be spaced apart therefrom. Afunction of the chamber 130 is to apply heat or take heat away from thememory so that it is in a hot or cold state. In order to move thechamber 130 up and down, as shown in FIG. 2, a vertical rack gear 150may pass through a rear portion of the chamber 130, and a gear (notshown) may be provided in the chamber 130 to engage with the rack gear150. The reason why the hot or cold state is thus provided to the memoryis because the memory is checked to be normally operated in an extremesituation so as to increase the reliability of a test.

The temperature display 160 individually displays the temperatureprovided to respective memories by the number of the memories to betested.

As shown in FIG. 3, each socket 115 mounted on the mounting unit 110 hasa concave adapter 116, and a plurality of pinholes 117 is formed in abottom of the adapter 116 in such a way that pins protrude from thesocket 115. That is, the adapter 116 is elastically mounted from below.Thus, if an adapter side is pushed a little, the adapter 116 moves downwhile the pins protrude through the pinholes 117. Since the pinsprotrude through the pinholes 117 into the adapter 116, the pins connectthe test memory to a block and thereby a precise test can beadvantageously carried out using direct heat transfer. This isdifferentiated from a conventional method wherein the test is carriedout using indirect heat transfer between the block and the memory thatoccurs through the ambient air.

The chamber 130 according to the present invention can be used for boththe hot test and the cold test. Another chamber is provided to be usedonly for the hot test.

First, the chamber for the hot test or the cold test utilizes athermoelectric element in common. This thermoelectric element will bedescribed below.

The thermoelectric element is a new generation cooling substrate whichcan simultaneously perform a cooling operation, a heating operation, aconstant temperature maintaining operation, and a power generatingoperation using just the supply of DC power with a thermoelectricmaterial, and can ensure convenient and reliable exchange between heatand electricity. This thermoelectric element is used as a substitute fora conventional cooling method that uses a compressor, thus enabling boththe cooling operation and the heat emitting operation to be convenientlyperformed anytime and anywhere. Thereby, according to the application oftechnology, in the case of the best specification, the temperature of aproduct can be freely adjusted and kept constant from between −75° C. toa maximum of +300° C. with an accuracy of ±0.03° C. In addition, it isan element that can carry out the cooling operation and the heatingoperation as soon as it is attached to a portion ranging from a smallportion of 0.8 cm wide×0.8 cm long to a wide portion, is anenvironment-friendly product which breaks with the use of Freon gas andhas higher quality than the products of other companies because it ismore convenient and precise.

If an on-off control method is used in the case of making a system usingsuch a thermoelectric element, this has a fatal effect on the life spanof the thermoelectric element, so that a product using “GM attachmenttechnology” needs to be utilized. That is, in the case of implementing areal system, it is difficult to selectively use only one of the coolingoperation and the heating operation. Therefore, according to the presentinvention, a special product using “GM attachment technology” isutilized as the thermoelectric element, thus remarkably improvingdurability.

Further, since the thermoelectric element is made of ceramic, itfrequently breaks down if the tightening force is excessive or isnon-uniform at four corners when assembling a cooling unit. Thus, a lotof care is required to assemble the thermoelectric element. A productmade of thin ceramic may be easily destroyed by external shock, and inaddition, may be broken even by external shocks during assembly.

Mechanical destruction of the thermoelectric element that is most widelyknown occurs when assembling the cooling unit. Thus, in order to solvethe problem, the present invention integrates the “GM attachmenttechnology” into the thermoelectric material to remarkably improve thestrength of the material. The test results are shown in the followingTable 1.

TABLE 1 electrical shock durability test [40/90 test] number ofmechanical time required experiments shock test thermoelectric forelement on element number of shocks element specification destructiondestruction [just before HMN 6040 standard [Time] [Cycle] destruction]before improvement 49.2 649 352 application of 3,795 45,002 7,756 GMattachment technology

As shown in FIG. 4, the hot/cold combination chamber 130 according tothe present invention is provided with blocks 131 which are insertedinto the adapters 116 of the corresponding sockets 115 so as to be putin close contact therewith. Thermoelectric elements 132 are seated onupper surfaces of the respective blocks 131, and a water jacket 133 isseated on the upper surface of the thermoelectric elements 132 to movecooling water therein. Also, a cooling fan 134 is provided in the waterjacket 133. The blocks 131 and the water jacket 133 are elasticallysupported at upper and lower portions thereof by vertical rods 139 thatare provided on opposite sides of the blocks 131 and the water jacket133. That is, the blocks 131 and the water jacket 133 are elasticallysupported by springs 139 a so as to mitigate shocks and adjust a contactforce of the block 131, when the chamber 130 moves downwards so thateach block 131 makes contact with the socket 115.

Such a block 131 includes an upper block 131 a that makes contact with alower portion of the thermoelectric element 132, and a lower block 131 bthat is located under the upper block 131 a to be inserted into thesocket 115. Further, in order to efficiently perform heat transferbetween the upper block 131 a and the lower block 131 b, a heat pipe 180extends integrally from an interior of the upper block 131 a to a lowerend of the lower block 131 b. Furthermore, a temperature sensor hole 136is formed in the lower block 131 b, with a temperature sensor 137disposed on a lower end of the temperature sensor hole 136. That is, thetemperature sensor 137 is placed adjacent to the lower end of the lowerblock 131 b, so that the temperature sensor 137 detects the temperatureof the lower end of the lower block 131 b and delivers it to thetemperature display 160.

Further, a plurality of discharge holes 138 is formed in a lower surfaceof the lower block 131 b. These discharge holes 138 inject nitrogen gasthrough the lower block 131 b towards the socket 115, thus preventinghumidity from occurring when performing the cold test. Thus, thedischarge holes 138 extend upwards from the lower surface of the lowerblock 131 b and then pass through both sides of the upper block 131 a tobe connected to a nitrogen generator that is on the exterior.

The water jacket 133 is a means for supplying cold air to the block 131,and blows the cold air, generated while circulating the cooling water,towards the block 131 using the cooling fan 134. The reason why the coldair is blown like this is because it takes a long time to reach a targettemperature using just the thermoelectric element 132 and it is easierto reach the target temperature if the cold air is blown together.Further, in order to efficiently control the heat, an insulator 132 a isinstalled outside the thermoelectric element 132. For reference,reference numeral “130 a” denotes a steel plate body of the chamber 130.

As shown in FIG. 5, the chamber for the hot test is provided with blocks141 that are inserted into the adapters 116 of the sockets 115 to comeinto close contact therewith. Thermoelectric elements 142 are seated onupper surfaces of respective blocks 141, and a heat pipe 180 is seatedover the upper surfaces of the thermoelectric elements 142, with aradiator 143 and radiation fans 144 seated on an upper surface of theheat pipe 180. Further, each block 141 and each thermoelectric element142 are surrounded by an insulator 148 to prevent heat from leaking.Furthermore, each block 141 includes an upper block 141 a that isdisposed just under the thermoelectric element 142, and a lower block141 b that is disposed under the upper block 141 a to be inserted intothe socket 115. Like the hot/cold combination chamber 130, a temperaturesensor hole 146 is formed in the lower block 141 b, and a temperaturesensor 147 is inserted into the lower end of the temperature sensor hole146. Thus, the temperature sensor 147 detects a temperature of the lowerend of the block 141 and delivers it to the temperature display 160.

The reason why the heat pipe 180, the radiator 143 and the radiation fan144 are separately provided above the thermoelectric element 142 isbecause this arrangement allows the target temperature to be morerapidly reached. In other words, it takes a long time to reach thetarget temperature using just the thermoelectric element 142. However,if heat is emitted using the heat pipe 180 and is transferred to pins ofthe radiator 143 and the radiation fan 144 blows hot air downwards, itis easy to reach the target temperature of each block 141.

In the drawing that shows the chamber 140 for the hot test, internalcomponents such as the blocks 141 are not illustrated as beingelastically supported like in the chamber 130 for the cold test.However, it is to be understood that the internal components can beelastically supported as shown in FIG. 4, although that is not describedin detail.

The test equipment 100 according to the present invention may furtherinclude a nitrogen generator. Nitrogen used in the cold test can besupplied from a location where the equipment is installed. However, ifthe nitrogen is not supplied smoothly, the nitrogen generator may beadded to the test equipment 100 itself.

As shown in FIG. 6, the nitrogen generator is installed to be disposedunder the mounting unit 110. Such a nitrogen generator 170 supplies onlyhigh-purity nitrogen gas of 99.999% or more with unnecessary gases suchas O₂, H₂O, and CO₂ being removed from the air using a carbon molecularsieve (CMS).

Since the CMS has high heat resistance, a wide specific surface area,and pore determining properties of a mesh structure, the CMS maintains apredetermined absorptivity even in the air that is low in water content,and thereby is suitable for applications in which the ultra-drying ofthe air is required. Further, the CMS has a specific surface area of 480m²/g, a water adsorption capacity up to about 22%, and a regenerationtemperature of about 200° C. to 320° C. The CMS is classified into CMSfor air and CMS for gas, according to the characteristics of a product.

Meanwhile, the heat pipe 180 used in the present invention has a specialstructural shape to ensure good heat transfer. That is, as shown inFIGS. 7 and 8, an evaporation cap 181 is mounted to one end of the heatpipe 180, while a condensation cap 182 is mounted to the other end ofthe heat pipe 180. Further, a wick 185 is provided in the heat pipe 180in such a way as to extend from the evaporation cap 171 to a middleportion of the heat pipe 180. As shown in FIG. 8, the wick 185 is madeof copper, and is fitted into the heat pipe 180 in such a way as to bein close contact with an inner surface of the heat pipe 180, thusmaximizing the evaporation and insulation of the heat pipe 180.

A specific example of the heat pipe 180 will be proposed in thefollowing. However, the heat pipe is not limited thereto.

TABLE 2 Specification of Heat Pipe component dimension (mm) materialwick length 450 copper mesh 180 thickness 0.02 heat pipe outer diameter9.52 copper inner diameter 7.74 thickness 0.89 length 1200 working fluidpurity (%) 99.9 water 5% (Vt) methanol 7.5% (Vt) total 12.5% (Vt)

The heat pipe 180 according to the present invention is manufactured sothat its evaporation portion is 410 mm, its insulation portion is 180mm, and its condensation portion is 610 mm to create an overall lengthof 1,200 mm. That is, when seeing an approximate ratio, the condensationportion is about a half of the entire heat pipe 180, and the insulationportion is about half as long as the evaporation portion. Thus, in theevaporation portion, a refrigerant is supplied with heat and is heated,so that the refrigerant is evaporated and vapor particles move towardsthe condensation portion at an acoustic velocity. Further, in thecondensation portion, the vapor emits condensation heat so that itbecomes liquid, and the liquid is returned by capillary force of thewick 185.

As described above, the present invention provides test equipment, whichenables Nand Flash Memory to be tested in both a hot state and a coldstate and thereby checks adaptability for various environments, thusenhancing the reliability of determining whether a product is defectiveor not.

Further, the present invention provides test equipment, which cansuppress the humidity that may occur in a cold test.

Although the preferred embodiments of the present invention have beendisclosed for illustrative purposes, those skilled in the art willappreciate that various modifications, additions and substitutions arepossible, without departing from the scope and spirit of the inventionas disclosed in the accompanying claims.

What is claimed is:
 1. Hot/cold test equipment for a Nand Flash Memory,comprising a mounting unit that contains the Nand Flash Memory togetherwith a socket to test whether the memory is defective or not, a chamberprovided above the mounting unit and moving up and down to come intocontact with the socket and thereby provide a target temperature, and atemperature display displaying the target temperature, wherein thechamber comprises: a block inserted into the socket; a thermoelectricelement seated on an upper portion of the block; a water jacket seatedon an upper portion of the thermoelectric element and circulatingcooling water therein; and a cooling fan provided in the water jacket toblow air downwards, with a discharge hole being formed on a lowersurface of the block to discharge nitrogen gas.
 2. The hot/cold testequipment as set forth in claim 1, wherein the block is elasticallysupported in the chamber.
 3. The hot/cold test equipment as set forth inclaim 2, wherein the socket comprises an adapter into which a lower endof the block is inserted, with pinholes being formed in a bottom of theadapter to cause pins making contact with the memory to protrude towardsthe block when the block is pressed against the adapter.
 4. The hot/coldtest equipment as set forth in claim 1, further comprising: a nitrogengenerator provided under the mounting unit to supply the nitrogen gas tothe discharge hole.
 5. The hot/cold test equipment as set forth in claim1, wherein the block comprises an upper block that comes into contactwith a lower portion of the thermoelectric element, and a lower blockthat is coupled to a lower portion of the upper block and is insertedinto the socket, and the heat pipe is provided between the upper blockand the lower block, and a temperature sensor is provided in an interioradjacent to a bottom of the lower block to be connected to thetemperature display.
 6. The hot/cold test equipment as set forth inclaim 5, wherein outer portions of the block and the thermoelectricelement are surrounded by an insulator.
 7. The hot/cold test equipmentas set forth in claim 5, wherein a wick made of copper is provided inthe heat pipe in such a way as to extend from an evaporation portion toa middle portion of the heat pipe.
 8. Hot/cold test equipment for a NandFlash Memory, comprising a mounting unit that contains the Nand FlashMemory together with a socket to test whether the memory is defective ornot, a chamber provided above the mounting unit and moving up and downto come into contact with the socket and thereby provide a targettemperature, and a temperature display displaying the targettemperature, wherein the chamber comprises: a block inserted into thesocket; a thermoelectric element seated on an upper portion of theblock; a heat pipe seated on an upper portion of the thermoelectricelement; a radiator seated on an upper portion of the heat pipe; and aradiation fan disposed above the radiator to blow air downwards.
 9. Thehot/cold test equipment as set forth in claim 8, wherein the block iselastically supported in the chamber.
 10. The hot/cold test equipment asset forth in claim 9, wherein the socket comprises an adapter into whicha lower end of the block is inserted, with pinholes being formed in abottom of the adapter to cause pins making contact with the memory toprotrude towards the block when the block is pressed against theadapter.
 11. The hot/cold test equipment as set forth in claim 8,wherein the block comprises an upper block that comes into contact witha lower portion of the thermoelectric element, and a lower block that iscoupled to a lower portion of the upper block and is inserted into thesocket, and the heat pipe is provided between the upper block and thelower block, and a temperature sensor is provided in an interioradjacent to a bottom of the lower block to be connected to thetemperature display.
 12. The hot/cold test equipment as set forth inclaim 11, wherein outer portions of the block and the thermoelectricelement are surrounded by an insulator.
 13. The hot/cold test equipmentas set forth in claim 11, wherein a wick made of copper is provided inthe heat pipe in such a way as to extend from an evaporation portion toa middle portion of the heat pipe.